This invention relates to the construction industry, specifically to the excavation of the material in confined areas. It is directed to use on hydraulic excavators and loader backhoes.
Contractors from the beginning of mechanized excavation have looked for ways to excavate earth and material from confined areas and, depending on the material being excavated, have looked for a bucket that would clean out with each scoop so that the excavation could proceed more efficiently.
The original buckets worked off of steam driven winches and wire rope cables. This design stayed basically the same until the 1960""s with the advent of hydraulic excavators.
Inventors then began to develop buckets based on the use of hydraulic power. U.S. Pat. No. 4,392,774 to Thomas (1983) discloses an attempt to develop a clam bucket using a single cable run through sheaves. The operating mechanism extends beyond the radius of the bucket limiting the accessible area of the attachment and making the arm susceptible to hanging inside a shored excavation. U.S. Pat. No. 5,228,735 to Morrow (1991) shows a clam bucket assembly which incorporates an elaborate linkage system, costly to manufacture and maintain. The hydraulic tubes are exposed, creating the possibility of breakage sending 180xc2x0 fluid spraying into the atmosphere and/or onto workmen. This unit gives no extended reach to work over objects. Also, it has no bucket cleaner. U.S. Pat. No. 4,257,731 to Beaver (1978) demonstrates a clam bucket that does not increase digging depth. The assembly requires extra hydraulics from the host machine and uses an elaborate linkage system to operate the bucket, thus raising the cost to the consumer. This design, again, has no bucket cleaner. U.S. Pat. No. 3,920,137 to McCain (1974) shows a clam bucket assembly designed with a very elaborate mechanism that is costly to manufacture and maintain and does not increase digging depth or reach, and this patent claims no bucket cleaner.
The above-referenced buckets suffer from a number of disadvantages:
(a) Expensive and elaborate linkage mechanism. Costly to build and maintain.
(b) All hydraulic requirements use an extra system which has to be added to the host mechanism at an added cost.
(c) None of the previously patented buckets have a self-cleaning bucket which allows the removal of wet and sticky material that becomes trapped in the bucket.
In accordance with the present invention, a self-cleaning bucket is described, comprising a bucket with a hinged wiper plate, a striker assembly, and an hydraulic cylinder operated by standard hydraulic circuitry.
The bucket, which is mounted on the excavator stick, has a hinged xe2x80x9croofxe2x80x9d, or wiper plate, which is designed to follow the inner contour of the sides of the bucket. The wiper plate is forced to the top of the bucket as the bucket fills with dirt or other materials. The bucket hydraulic cylinder rotates the bucket, causing the wiper plate to come in contact with striker forks mounted on the excavator stick, thereby forcing the wiper plate downward, ejecting the dirt or other materials from the bucket.
Objects and Advantages
Accordingly, the objects and advantages of the self-cleaning hydraulic bucket are:
(a) a hydraulic bucket that requires no additional hydraulic circuitry to operate.
(b) self-cleaning bucket. The bucket cleans its internal dimension upon each dumping cycle, thus removing all types of material which stick and are packed into the bucket upon filling.
(c) workers do not have to manually clean out the bucket, lessening their exposure to contaminated materials and hazardous wastes.
(d) no elaborate mechanical linkage to maintain and wear out.
Further objects and advantages of the self-cleaning hydraulic bucket will become apparent from a consideration of the drawings and ensuing description.